Thought It Was Fixed Still Runnin Rich Code 91 Only

joedirt76 · Mar 4, 2014

I don't think this is a normal problem ,this is gonna be long but please read and help , after lots of electrical test part swapping and replacing I am still running rich . as of now I am not using the pms it is on the bench stock computer only (a9p) , 36 # injectors replaced with 30# , correct calibration tube being used, maf properly cleaned , spark plugs are autolite 3924 gapped at .054 , base idle correct and tps at .99 , timing 14 degrees,o2 sensors replaced, o2 sensor harness completely continuity checked, all grounds checked and good , maf,map,and tps sensor checked and good . after all that I am pulling (code 91 only) and it just wont go away , ive cleared codes in ever fashion including battery disconnect to clear kam redrove reran test and 91 just wont go away , car starts and runs ok but is runnin rich enough the smell bothers u at idle , heres the kicker after parts replacement injectors , computer, plugs, and bypass pms ,the car ran so perfect I couldn't believe it !! but only lasted for that one run the next time I cranked 2 days later it was right back to runnin rich , please please help I am at total lost at this point , thanku in advance

84Ttop · Mar 4, 2014

Are you using a C&L Meter?

joedirt76 · Mar 4, 2014

I am currently, I know everyone says there junk and pro-m supposed to be the way to go , due to lack of funds I haven't purchased one yet. I certainly don't know it all and hope to not offend anyboby in my lack of knowledge on some of this , but how can the meter alone throw that code , theres nothing electrical about it I would think maf sensor before the meter but then why not code 41 with it ?

joedirt76 · Mar 4, 2014

just to be clear my mass air flow is a 76mm c&l with tube 099 for 30# injectors , the meter itself that plugs into harness is a stock meter

Grabbin' Asphalt · Mar 4, 2014

IMO the meter is critical in the amount of air/fuel mixture, .....so it is the BIG part on the air side to determine the Fuel side, any screw up in that dept and problems abound.

Bullitt347 · Mar 4, 2014

The reason C&L meters have this issue is that they are trying to "trick" the stock MAF sensor into reading a certain amount of air flow. The stock sensor was calibrated for 19 lb/hr injectors, with the C&L meter, the sensor is still calibrated for 19 lb/hr injectors, but C&L is using a different sampling tube to get a different air flow across the sensor to offset the larger fuel injectors. Sometimes it is close enough, sometimes not so much.

joedirt76 · Mar 4, 2014

good explanation that makes sense , but how is a pro-m gonna solve the problem if im still using 30# injectors and the sensor is still calibrated for 19#

Bullitt347 · Mar 4, 2014

joedirt76 said:
good explanation that makes sense , but how is a pro-m gonna solve the problem if im still using 30# injectors and the sensor is still calibrated for 19#

Because the Pro-M does not use a MAF sensor calibrated for 19 lb/hr injectors. They actually calibrate the sensor to the size injector you are using so there is no "tricking" of the sensor. The electronics inside the sensor have been changed (the air/fuel map or table is recalibrated) instead of changing how the air flows past the sensor.

joedirt76 · Mar 4, 2014

ahhhhh haa, 10/4 guess ima have to invest your the first one who has explained it in a way that I understand , makes total sense now especially being it has always ran rich since the build , I will get one, and I will reply with a update to this thread as soon as installed !! thanks a bunch

Bullitt347 · Mar 4, 2014

Glad I could help, keep us posted.

joedirt76 · Mar 12, 2014

was gonna wait till weekend to give better update , but bought pro-m 80 installed last night , put computer back in that I let sit on bench and decay in codes hookup up scanner cleared codes again and turned the key , right away running completely different and as much as I hate to say its worst after meter change,still running rich I didn't mess with it long only long enough to warm up and run a koer to pull codes , 91 is gone for now only pulled 3 others and that's the stuff unplugged egr,thermatic etc. but still running rich , im starting to wonder if im just overfueling somehow ,too much fuel pump,or jacked up regulator maybe ?

jrichker · Mar 12, 2014

What were the numeric codes?

joedirt76 · Mar 12, 2014

was in a hurry didn't write them down ,but I do remember 94, I will have better update and info this weekend ! work has me tied down till then

madspeed · Mar 12, 2014

to clarify, you now have a pro m meter calibrated for 30# injectors along with 30# injectors?

joedirt76 · Mar 12, 2014

Yes sir

madspeed · Mar 12, 2014

do ou have a wideband o2 sensor and an afr gauge?

joedirt76 · Mar 12, 2014

No , just replaced o2's with new stock Bosch ones

joedirt76 · Mar 12, 2014

Was gonna try next checking my fuel pressure with different gauge just to confirm if pressure is correct or not , right now I have small gauge tapped right into pressure regulator but want to rule out if that gauge is defective or not

madspeed · Mar 12, 2014

If no wideband how are you sure its rich?

joedirt76 · Mar 12, 2014

FUMES, bout died lastnite just letting it warm up lol

Thought It Was Fixed Still Runnin Rich Code 91 Only

Member

They make new pistons every day, so why worry?

Member

Member

I have been doing it wrong this whole time

Member

I have been doing it wrong this whole time

Member

I have been doing it wrong this whole time

Member

StangNet's favorite TOOL

Member

Colonel Mustard

Member

Colonel Mustard

Member

Member

Colonel Mustard

Member

Similar threads

Privacy & Transparency

Privacy & Transparency